Staple driving machine



Sept. 20, 1949. e. A. CROSBY ET AL STAPLE DRIVING MACHINE 4 Sheets-Sheet 1 Filed Nov. 2, 1,945

Sept. 20,- 1949. G. A. CROSBY ET AL 2,432,155

STAPLE DRIVING MACHINE Filed Nov. 2, 1945 4 Sheets-Sheet 2 7 97550 6 1 z 422 6667 6 9 9 7%o0/ h Sept. 20, 1949. e. A. CROSBY ET AL 2,482,156

STAPLE DRIVING MACHINE G. A. CROSBY ET AL STAPLE DRIVING MACHINE Sept. 20, 1949.

4 Sheets-Sheet 4 Filed Nov. 2, 1945 flamed f 6 2/1 m),

Patented Sept. 20, 1949 2,482,156 STAPLE DRIVING MACHINE George A. Crosby,

Ericsson, Chicago, 111.,

Steel Strapping Company, poration of Delaware Park Ridge, and Arvid I.

assignors to Signode Chicago, 111., a cor- Applioation November 2, 1945, Serial No. 626,267

3 Claims.

Our invention relates to staplers.

More particularly it relates to a staple driving tool, preferably operable by a hammer or mallet, for seating relatively large or heavy duty staples, such as are used in a wide variety of situationsone example being to embrace metallic box strapping to retain the same in place.

One of the objects of our invention is to provide an improved stapler of the type mentioned above.

Another object is to provide magazine type which may loaded with staples.

Another object is to provide a stapler which will not easily jam from improperly fed or driven staples.

A further object is to provide a stapler which is simple, effective and rugged.

Other objects and advantages will hereinafter appear.

The preferred embodiment illustrated in the accompanying drawings,

Fig. 1 is a side elevation of the stapler;

Fig. 2 is a section on the line 2-2 of Fig. l;

a stapler of the be conveniently of our invention is where- Fig. 3 is a section on the line 3-3 of Fig. 1; Fig. l is a section on the line tl of Fig. 1; Fig. 5 is a section on the line 5-5 of Fig. 4;

Fig. 6 is a top plan of the forward end of the stapler;

Fig. 7 is a front elevation showing some of the normally hidden parts in dotted lines;

Fig. 8 is an irregular vertical cross section;

Fig. 9 is a bottom plan;

Fig. 10 is a vertical section through the front end of the stapler, showing the parts in stapleloading position; and

Fig. 11 is a front elevation, also in loading condition.

In general, our stapler includes a frame adapted for restin upon or against the surface of Whatever the staples are to be driven into-such, for example, as a box-and which includes a magazine for holding a plurality of staples. lhis frame carries a movable driving head, especially adapted to be struck by a hammer or mallet and carrying a staple driver, which engages the staples after they have been ejected from the magazine, and forces them into the work under the impact of the hammer or mallet. The frame also carries a pivotally mounted gate which, when in closed position, retains the staples in the magazine and governs the ejeotment thereof so that they are sequentially presented, only one at a time, to the driver,

but which may be swung to r an open position to permit the staples, preferably in the form of a stack or stick being inserted into the magazine.

Referring particularly to Figs. 1, 8 and 9, the stapler includes a frame 5 formed in part of two complementary sections 6 and I which fit together along a medial vertical plane and are securely clamped in that relation by suitable means including screws 8. The sections are provided with complementary openings which, when the sections are assembled, form a convenient handheld 9 for carrying the tool and holding it in proper position upon or against the work during operation. For the sake of lightness, these frame sections may preferably be aluminum die castings.

Section 6 is made somewhat shallower than section l, as most clearly shown in Figs. land 2, to provide, in effect, a longitudinal recess along one lower side edge for accommodating a long staple storage bar ill, which is substantially U cross section of a size to be straddled by the staples .8. At the forward end of the tool a staple guide block l l fits between the depending legs or flanges of bar ill. The front face 52 of this block serves to support the yoke or crown of the staples against bending rearwardly while they are being driven into the work, as will be explained later. Staple storage bar Ill is rigidly attached to frame section I by a cleat l3 and screws 54, which thread into frame section I. Spacer sleeves i5 surrounding screws M and fittin between the flanges of bar iii prevent the inward collapse of these flanges and render the attachment of the staple bar to the frame more rigid. A similar screw 26 and, if desired a pin ll, serve in part to hold guide block H in its place between the storage bar flanges and to anchor both the bar and guide block to frame section l. Thus the lower edges of frame section '5, staple bar it, and block ll constitute an effective base for resting the tool against the surface of the work into which staples are to be driven. And the frame and storage bar H3 form a magazine for holding a considerable number of staples, which, as will be hereinafter explained, are automatically fed forwardly as they are one by one driven into the work. During the driving, the legs of the staples are prevented from being spread apart by a U-shaped outer side-guide IS, the yoke and depending side flanges 28 of which straddle bar it and are spaced away therefrom sufficiently to permit staples to slide readily therebetween. The forward front edges M of outer guide is lie in advance of the front face l2 of block it slightly more than the thickness of the staples so that the legs of the staples are supported thereby against lateral bending and spreading. Guide I8 is rigidly held in place by suitable means, such as rivets 22 passing therethrough and through block l I and the flanges of bar I0.

The staples are urged forwardly along magazine bar l ti.e., to the right as viewed; for example, in Figs. 1 and 8by a U-shaped staple follower 25, which straddles the staple storage attachable and detachable connection; may be attained by securing a link 28 to the free end of spring 25, such as by a rivet 29, and providing in" this link a bayonet or tapered slot for fitting over a headed post 39 formed as a part of and probar and bears against the rearrnost staple in the.'10.-

magazine. Follower 25 is biased onurgedt-forjecting upwardly from the rear edge of follower 25, as shown most clearly in Figs. 1, 8 and 9.

The coiling of spring 26 about spindle 27, and

consequently the intensity of the staple feeding action of follower may be rendered adjustableby providing for the rotational adjustment of this spring anchoring spindle. As shown most clearly in Figs. 4? and 5. anenlarged head 3| of spindle 27! is journaled in a bore through frame section 6 and a reduced shank 32 is journaled in a bore through frame section 1. A diametrically disposed slot 33 inspindle 27 receives the end of the coiled portionqof spring 26 so that as the spindle is rotated in one direction or the other, the springis wound tighter or looser as the case may be. A spring 34 bearing atone end against a beveled shoulder 35 on spindle 21 and at the other end against a shoulder 35 of frame section 7 biases the spindle outwardly-i e., toward the right as viewed in Figs. 4 andB-normally to seat a cross pin 37 carried by the spindle in a cross slot 38 formed in the outer surface offrarne section '3. Thus when spindle 27 is pushed inwardly far enough to cause cross pin 3i to be forced out of slot 38, the spindle may then be rotated in either direction to tighten or loosen feed spring 26; A screw d i er slot 39 may be provided inspin-dle 27 to facilitate its rotat on. When spindle Eli-has been rotated sufficiently to insure the desired tension in feed'spring 26; the release of the endwise pressure upon it will permit biasing spring 3% to move the spindle outwardly to-cause cross pin 3'! to re-enter slot 38 and thereby lock the spindle in its adjusted position to retain the staple feeding spring at its adjusted tension. 7

A latch is provided to retain the staple follower 25 in its rearinost' position-i. e., to the extreme left end of its travel, as viewed in Figs. 1 and 8- during the staple loading operation or whenever for; any reason iti-s desirable to; relieve the stored staples of the feeding bias of spring 26; This latch comprises a. stud l5 slidablyretained in aligned holes in the flanges of magazine: bar I 0. One end of stud 55 is enlargedto form a; head at which, when follower 25 is in fully retracted position, is projected by a spring 47 into a hole 48 in theouter flange of the follower, therebyiatching it against movement until the stlldls pushed inwardly by the operator. To facilitate theoperators retraction of follower 25 preparatory to loading the magazine with staples and to render the latchin'g of the follower in that position automatic, its outer flange is provided with-arlaterally projecting lug Eli-which may be readily: engaged by the operators finger or thumb. And by forming lug 5% with a cam-like surface 5| to engag the beveled portion 52 of the head of stud 45, the mere retraction of the follower will cause the latching stud to be pushed inwardly. Thereupor the flange of the follower will hold the stud retracted until theihole iii in the follower registers with the stud, whereupon spring t? will project the head 4% of the stud into the hole of the follower and the follower will be held back until the operator pushes stud 45 inwardly.

The staples are retained in the magazine by a pivoted gate- 55 which in the normal operative condition of thetool is in the position shown best in Figs. 1? and 8 but which when the tool is to be loaded with staples may be swung downwardly intothe positionbest shown in Figs. 10 and 11. The gate is of substantially U shape having an arched yoke or front wall 56 and side flanges 57. The arched shape of th front wall is to conform to the shape of the: staple driverexpiainedilater. It is; pivotally attached to the frameworkqby a pin ttwhich is fixed at opposite ends in its fiansesB-l and lies a slot 59 in staple guideblock II. The top of slot 55, is closed by the-flangesof guide it. 'When. in its normal operative-position; gate 55 is retained in thatcondition by: a; springbiased latch which includes'a pair of release leverstg65, one located at each side of the tool. and pivoted thereto bya pin 65. This pivot pin 66 of the-two release levers s5 is retained against longitudinal movement. in the'tool frame by'a driver blade stop dog as will be later explained. Bridged= between these twolevers E5 is; a; rectangular. latch-bar 6i and a cylindricalreliefpin 68. Theeoppositeends of bar 67 are cylindrical in shape and like-the ends of pin 68 pass through levers 65. Both the latch bar 67 and relief-pin Gdare attached to release levers by having'their opposite-ends extended through the release bars and then upset over rivets stand 70, respectively. Latch bar 51 which, as previously stated; and-g shownlmost clearly in Fig. 8, is of rectangular cross section except whereits ends pass'through levers- 65 is adapted to fit. rather loosely into notches H formedin the upper edgesof theside flanges 51 of staple gate 55 to latch the gate in its normal operative position, as will be later explained. Latch bar 6? is biased downwardly into latching position by a spring 12. Spring 72 is located. in a socket 13 formed in the frame by complementary cavities, in frame sections 6 and 7. This spring is seated atone end against the bottom,

of socket 13 and at the other end against latch bar 8?. A pin 14 projecting from latch bar tl'into the bore of spring '12 serves to prevent-binding during operations ,of the latch. Thegate release levers may have their free orrear ends formed into suitable projecting ears F5 to be engaged, for example by the thumb and forefinger of one hand of theoperator to facilitate elevating them to raise the latch bar from notches l'l andthereby free the staple gate for swingingto open position.

The'relation of the latch and staple gate will now be-explained. Each flange 51 of gate. 55. is provided. at its rear upper corner with a curved or cammed surface 86. Forwardly of notch. H

eachgate flange also has a lug 8i with an inclined or wedge-like-surface 32. The front corners of gate 55 are provided with notches'84 which may register with and receive projections extending forwardly from: the front lower corners of the flanges of outer-staple guide, l8. These notches form shoulders 86 in the'yoke of gate-55 which, whenthe gate is :lnnormalclosed. position, abut projections 85 to prevent the gate from swinging downwardly. In order that gate 55 may be swung downwardly about its pivot 58 to load the magazine with staples, it is, therefore, first necessary to move it forwardly to disengage shoulders 88 from projections 85; but this movement cannot be effected until latch bar 81 has been raised from notches 'l I. However, when the inner ends of latch levers 85 are raised against the tension of spring 12 to withdraw latch bar 61 from notches II, then the gate can be pushed forward until its front wall shoulders 88 are moved out of register with projections 85; and then the gate can be pivoted downwardly to the position shown in Figs. and 11. In this position of the gate the magazine is open for the insertion of staples from the front of the tool. The gate is closed by swinging it upwardy and rearwardly so as to bring its pivot 58 toward the rear of slot 59 and cause the rounded cam surfaces 88 at the upper rear corners of flanges 51 to engage and raise latch bar 81 and also the free ends of latch levers 65 against the biasing force of spring 12. This movement of the gate again brings its notches 84 into register with projections 85 whereupon a slight rearward movement of the gate causes the projections 85 again to engage the front wall shoulders 88 thereof and retain the gate closed. In this condition the relief pin 88 carried by latch levers 65 is caused to press down upon the inclined surfaces 82 of ears 8|. The wedging action between pin 88 and inclined surfaces 82 holds the gate tightly in its normal position and yet affords a slight amount of forward movement in the event excessive forward strain comes upon the gate, such as might be occasioned by a staple becoming wedged in between the front wall or yoke thereof and guide block I I.

The staple driving mechanism includes a driving lever 98 carried on a pin 9| and lying between frame sections 8 and I by which it is to some extent supported against lateral displacement. Pin 8| is journaled in suitable aligned bores through frame sections 8 and I. The pin is retained in place by a lock wire 92 which has its opposite ends seated in holes in the pivot pin 9| and lever 98, respectively, as shown most clearly in Figs. 6 and 8. Driving lever 88 is biased toward its outer or retracted position, shown in Figs. 1 and 8, by a leaf spring 83, one end of which is anchored to the frame by screws 94 and the free end of which engages the underside of the driving lever. At its outer end driving lever 98 is enlarged into an impact head 95. This enlarged head is for receiving the blows of a mallet or hammer whereby the staples are driven.

The head of driving lever 98 is hollowed out, as best shown in Figs. 8 and 10, to form a rounded bottom socket I88 for receiving one end of a staple driver I8I. A screw I82 passing rather loosely through a hole in driver I8! and threaded into head 85 serves to prevent the driver from becoming disengaged from the driving head. The connection between head 95 and driver blade I8I is essentially a ball and socket joint to prevent binding therebetween during the up and down (outward and inward) movements of operation, and to permit a limited lateral forward and backward swing of the lower end of blade I8I for a purpose to be hereinafter explained.

Staple driver I8I is in the form of an elongated steel blade rectangular in cross section throughout its upper end but having its lower end of trapezoidal cross section to increase its strength and fit the curvature of the front wall of gate 55,

Fig. 9. There is thus I83, as most clearly as shown most clearly in provided stop shoulders shown in Figs. 1, '7 and 8. On the down (inward) stroke of the driver head and driver blade this stop shoulder I83 strikes the top of gate 55 to limit the downward (inward) movement, or staple driving stroke, of the driver blade so that the staple is fully driven into the work but the work surface is not marred or otherwise injured by the driving end of the blade striking it.

The staple driver blade I8I is provided with an elongated lengthwise slot I85 which cooperates with a stop dog I88 to limit the upward (outward) travel of the blade to either of two positions, one of which permits staples to be ejected from the magazine and the other of which blocks ejectment, as will now be explained.

Driver blade stop dog I88 has two vertically spaced shoulders I81 and I88 as most clearly shown in Figs. 8 and 18. Shoulder I88 is provided by a finger I89 which forms a rearwardly or inwardly extending arm of dog I88. When the lower end of driver blade I8I is swung to its rearward position, the lower end of its slot I85 is in a path of travel to strike shoulder I88; when the lower end is swung forwardly, its path of outward travel or retraction is such that the bottom of slot I85 will strike stop shoulder I81. In normal operation of the tool with gate 55 closed, the lower end of the driver blade is held in its rearward position so that shoulder I88 lies in the path of the bottom of slot I85 in the driver blade whereas shoulder I8! is out of that path. Thus when the spring 93 retracts the driving lever and blade following a mallet or hammer blow, the blade is retractedi. e., raised-far enough to clear the path of staples being ejected. If, however, the gate is open and staples in the magazine are being urged forwardly by the follower 25, the lower end of the driver blade will be swung forwardly while it is depressed because the gate is not there to hold it back as indicated by the dot-dash lines of Fig. 10. Then shoulder I8! is in the path of the bottom of slot I85 and the return of the driver blade will be arrested in its upward travel in a position blocking the ejectment of staples. This blocking of the staple ejectment path by the driver blade prevents staples from the magazine being ejected in the event the operator opens gate 55 to place additional staples in a partly filled magazine but forgets to retract and latch back the staple follower.

As previously mentioned, driver blade stop dog I88 serves the additional function of retaining the release lever pivot pin 68 in place in the tool frame against longitudinal movement. This is accomplished by forming pivot pin 86 with a center section III of reduced diameter, as shown most clearly in Fig. 7, the two end sections being of a diameter only sufficiently less than the size of the holes in the frame and release levers 85 to enable the pin to be forced into placev Spring III which is seated in a socket in the frame and bears against the finger I89 of dog I88 biases the dog outwardly so that the hole therethrough is concentric to the reduced mid section of pivot pin 68, thereby preventing the pivot pin from moving endwise. This method of retaining the release lever pivot pin in place is an aid in assembling the tool.

Briefly to summarize the normal operation of the tool, the staples in the magazine are urged forwardly by the spring pressed follower 25. They are moved forwardly until the front staple strikes the forward outer corners of gate 55 where it is 7i iirfthezpathiof the staple'drive'r blades, A-blow offaamallet'or hammer uponth'e head 95 of the dimer? lever? .k'flsforces that-front .staplei downe wardly into' therworkz Inaits movement from the line: of: the magazine down to and intothe worn the staple being driveniis supportedl'by the gate byfouter' guide: l8 'and :by the front'fa'ce of guide bliicki' 1.. Thedownior work stroke of thedriver blad' i's limited by itsshoulder: I03 engaging; the top edge of gate55r. When the forcerof thethammen blow has been expended, retractori spring 9-3? snaps the blade. and driver" lever back. into normalxposition' where. shoulder I08 of stop 'dog I06: strikes 1 the lower: end o'f" the driver blade slot 105i Inrthis-condition the-lower end of thevdriver bladei'is above the line of movement of'the staples in the magazine.andithe' spring biased follower 2'5'slides' the staples in the magazine forwardly until'lanother staple. is in the. pathofthe driver blade; I -his sequence of operations'is repeated eaclrtime the. driver head 'iSi struck by the. mallet orih'ammer.

Irr:order to replenish the magazine the operator should first retract follower 25*and permit it to be'*'automaticallylatched in its rearmost position byithe spring biased latch stud 45 entering the hole therein; In this way thestaple advancing biasof the follower is relieved and's'taples: may be now easily: loaded into the magazine. Then by'raisingsthe rear or free ends of release 65, gate 55will be unlocked by the raising of latch bar' from its notches-H. Now the gate may be moved forwardly'to clear its shoulders 86- from projections- 85 and then swung downwardly to open position: A supply of staples+-for" convenienc'e: usually initheform of stacks or sticks lightly, held together by suitable adhesive-may now be-placed in the magazine from. the forward end of the tool; When the magazine hasbeen filled to the desired extent gate 55 is swung upwardly and rearwardly to closedposition. In this movement cam surface 80 momentarily raises latch bar 61 against the bias of its spring "until notches 1| register. with the latch bar. Thereu'pon spring 72 forces thelatch bar into notches H and the gate'is latched against accidental'opening. And the action of retaining pin 68 upon the wedge surfaces 82 of the gate insuresthat the shoulders 86 of the gate firmly, but with some capability of give: under excessive strain, bear upon projections:85: V

The preferred methodof opening gate 55' for replenishment of staples-in the magazine is for the operator to grasp the tool with the driver lever in the palm of one hand and with the thumb and fingers of the same hand grasping the two release levers by their projecting ears [5. The other hand is thereby left free to manipulate the gate," as previously explained, to open it. In this manner the pressure between the palm and fingers of the hand pressing downwardly on the driving lever and pulling upwardly on the release levers will cause the driver lever to be pushed downwardly far enough to bring the end of the driver blade beyond the path of travel of the staples from the magazine. And should the operator have forgotten first to retract and latch baclc the follower, the pressure of the follower spring will cause theforemost of any staples remaining in the magazine to engage the driver bladeand swing its lower end outwardly so that the bottomof its notch I05 is engaged by shoulder Hl'l'of the driver blade stop dog. In this manner the driver blade is-retained in position to block the path ofstaple ejectment-from the magazine levers 8 V and staples: will-. not be inadvertently; throwneout of. the magazine when the:ga-te is 'open'ed:

Having; thusillustrated? and: explained: the nature and. one: embodiment of:- our: invention; what we claim" and desire to secure? by United States Letters Patentris as follows:

l. Infastapler, th'ex combination witn'a frame for" resting against an' object into which'astaples aretolbe driven; a magazine in th-eafranrevfor holdingia pluralityof staples sideby side andzhavign a staple ejection opening at one. end mea-nsfor moving staples: in the magazine" towarwithe staple ejectioniopen'ing, there'ofi; and-,a-=- staple driver pivotally carried by the frame-forengaging staples after ej'ectrnent from the magazine; of la gate-pivoted1to1the frame andmovableto a-posi-ztion for blocking the path of .ejectment of-istaples from the 'magazineto' .onestaple at atime andfor guiding the, staple driver against" the: ejected staple and-also movable to a position whereethe magazine is openfor the insertion of. staples thereinto, the frameand gate having cooperating projections and'shoulders for supporting andlre; taining the gate initsstap-leblocking. and. iver guiding;- positicn but: per itting the gates after. a forward movement to swing, toopenipositi a manually actuated latch normally located in. a notch in the gate to prevent-forward movement of the gate sufficicntto'enable the cooperating projections and-shoulders of theframe andL-gate to be disengaged andltlfereby. prevent-the gate from being swung open,- aspringnormally. biasing the latch to position to. prevent fbrvtarcfrhove:

ment'of the gate andua release lever bywliich the operator may withdrawthe latch fromv the notch inthegate andtherebypermit thegat'e to be moved forwardly to disengage-saidprojections and shoulders so that the gate maybe swung'to open position. I

2. In a stapler having a frame for resting against an object into which staples are to be driven, a magazine in the frame plurality of staples arranged side side. and provided with a staple ejecting opening atone end, a spring driven follower for urgingrstapleslin the magazine toward and through theeje'cting opening thereof, an actuating, lever carried" by the frame, a spring for biasing the actuating leveroutwardly away from the magazine ejecting opening, a staple driver blade pivotally attached to the actuating lever so. as to be movablelater'ally as well as longitudinally, and a gate associated with the frame and movable to: a closed-position blocking the path of staples elected from the magazine to limit. ejectment to one staple at. a time and guiding the staple. driver blade. in its inward longitudinal. movement against the ejected staple and also movable toanopenposi, tion where it no longer. guides the'driver blade and the magazine is open for insertion of: staples thereinto through the ejecting opening thereof; the combination of upper andlower stops carried by the frame-andlyingin different .planes. relative to both the longitudinal and lateral movements of the staple driver blade, the gate when .in closed position keeping the driver blade awayfromthe lower stop so that the upper stop arrests. the retraction of the driver bladebeyond the ejecting opening of themagazine'but when in open position permitting the pressure of the follower. to swing the driver blade laterally into; position to be engaged by the lower. stop to arrestthe retraction of the driver .bladetoblock the ejection of. staplesas the gate is opened.

3. A stapler having in combination a frame for holding. a r

or resting against an object into which staples ire to be driven, a staple magazine provided with t staple ejecting opening and for holding a plu- 'ality of staples side by side in alignment behind ;he ejecting opening, a spring driven follower for irging staples in the magazine toward and out of she ejecting opening thereof, an actuating lever pivoted to the frame and movable inwardly and outwardly relative to the staple ejecting opening of the magazine, a spring for biasing the actuating lever outwardly, a staple driver blade pivotally attached to the actuating lever so as to be movable longitudinally thereby and also capable of some lateral movement, and a gate carried by the frame and movable to a position blocking the path of ejectment of staples from the magazine to one staple at a time and guiding the staple driver blade in its inward movement against the single ejected staple to drive it and also movable to an open position where it no longer guides the driver blade and the magazine is open for insertion of staples thereinto through the ejecting opening thereof, characterized by a stop against which the gate in closed position directs the driver blade in its outward movement to arrest retraction of the driver blade beyond the path of staple ejectment from the magazine and by another stop laterally displaced from the first mentioned stop and against which the driver blade is directed by the follower in the outward movement of the driver blade when the gate is open and not guiding the driver blade so as then to arrest the retraction of the driver blade in the path of staple ejectment from the magazine and thereby block the ejection of staples as the gate is opened.

GEORGE A. CROSBY.

ARVID I, ERICSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,996,640 Case Apr. 2, 1935 2,083,227 Drypolcher June 8, 1937 2,095,659 Cavanagh Oct. 12, 1937 2,298,123 Harred Oct. 6, 1942 2,310,529 Krantz Feb. 9, 1943 2,342,818 Polzer Feb. 29, 1944 2,357,737 Harred Sept. 5, 1944 

